In 77 AD, Marcus Didius Falco, private "informer" and stalwart Roman citizen, undertakes one of the more fearsome tasks of his career, in this 19th mystery of the series—he goes on vacation with his somewhat pregnant wife Helena Justina and their two young children. They travel to Alexandria, in exotic Egypt, and aren't there long before the city's Librarian is found dead under suspicious circumstances, in his office with the door locked from the inside. Falco quickly finds himself on the trail for dodgy doings, malfeasance, deadly professional rivalries, more bodies, and the lowest of the low—book thieves.

"While on vacation with his family in Alexandria, Egypt, Falco is stunned to get word that Theon, the Great Library's head librarian, with whom he just dined, has been found dead with neither marks of violence on the body nor evidence of how the killer got away from the scene of the crime. Falco probes the academic politics surrounding the Great Library to determine whether one of Theon's potential successors was the culprit. Other deaths follow, including that of a philosophy student, mauled by a crocodile that escaped from the local zoo.... The twisty plot with its various false leads and the author's plausible depiction of ancient Alexandria make this one of the stronger entries in this solid historical series."—Publishers Weekly